/*
  Copyright (c), 2001-2022, Shenshu Tech. Co., Ltd.
  Copyright (c), 2001-2022, Shenshu Tech. Co., Ltd.
 */
#ifndef TEE_CLIENT_API_H
#define TEE_CLIENT_API_H

#ifdef __cplusplus
extern "C"
{
#endif

#include <limits.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

/*
 * Defines the number of available memory references in an open session or
 * invoke command operation payload.
 */
#define TEEC_CONFIG_PAYLOAD_REF_COUNT 4

/**
 * Defines the maximum size of a single shared memory block, in bytes, of both
 * API allocated and API registered memory. There is no good value to put here
 * (limits depend on specific config used), so this define does not provide any
 * restriction in this implementation.
 */
#define TEEC_CONFIG_SHAREDMEM_MAX_SIZE ULONG_MAX

/**
 * Flag constants indicating the type of parameters encoded inside the
 * operation payload (TEEC_Operation), Type is uint32_t.
 *
 * TEEC_NONE                   The Parameter is not used
 *
 * TEEC_VALUE_INPUT            The Parameter is a TEEC_Value tagged as input.
 *
 * TEEC_VALUE_OUTPUT           The Parameter is a TEEC_Value tagged as output.
 *
 * TEEC_VALUE_INOUT            The Parameter is a TEEC_Value tagged as both as
 *                             input and output, i.e., for which both the
 *                             behaviors of TEEC_VALUE_INPUT and
 *                             TEEC_VALUE_OUTPUT apply.
 *
 * TEEC_MEMREF_TEMP_INPUT      The Parameter is a TEEC_TempMemoryReference
 *                             describing a region of memory which needs to be
 *                             temporarily registered for the duration of the
 *                             Operation and is tagged as input.
 *
 * TEEC_MEMREF_TEMP_OUTPUT     Same as TEEC_MEMREF_TEMP_INPUT, but the Memory
 *                             Reference is tagged as output. The
 *                             Implementation may update the size field to
 *                             reflect the required output size in some use
 *                             cases.
 *
 * TEEC_MEMREF_TEMP_INOUT      A Temporary Memory Reference tagged as both
 *                             input and output, i.e., for which both the
 *                             behaviors of TEEC_MEMREF_TEMP_INPUT and
 *                             TEEC_MEMREF_TEMP_OUTPUT apply.
 *
 * TEEC_MEMREF_WHOLE           The Parameter is a Registered Memory Reference
 *                             that refers to the entirety of its parent Shared
 *                             Memory block. The parameter structure is a
 *                             TEEC_MemoryReference. In this structure, the
 *                             Implementation MUST read only the parent field
 *                             and MAY update the size field when the operation
 *                             completes.
 *
 * TEEC_MEMREF_PARTIAL_INPUT   A Registered Memory Reference structure that
 *                             refers to a partial region of its parent Shared
 *                             Memory block and is tagged as input.
 *
 * TEEC_MEMREF_PARTIAL_OUTPUT  Registered Memory Reference structure that
 *                             refers to a partial region of its parent Shared
 *                             Memory block and is tagged as output.
 *
 * TEEC_MEMREF_PARTIAL_INOUT   The Registered Memory Reference structure that
 *                             refers to a partial region of its parent Shared
 *                             Memory block and is tagged as both input and
 *                             output, i.e., for which both the behaviors of
 *                             TEEC_MEMREF_PARTIAL_INPUT and
 *                             TEEC_MEMREF_PARTIAL_OUTPUT apply.
 */
#define TEEC_NONE 0x00000000
#define TEEC_VALUE_INPUT 0x00000001
#define TEEC_VALUE_OUTPUT 0x00000002
#define TEEC_VALUE_INOUT 0x00000003
#define TEEC_MEMREF_TEMP_INPUT 0x00000005
#define TEEC_MEMREF_TEMP_OUTPUT 0x00000006
#define TEEC_MEMREF_TEMP_INOUT 0x00000007
#define TEEC_MEMREF_WHOLE 0x0000000C
#define TEEC_MEMREF_PARTIAL_INPUT 0x0000000D
#define TEEC_MEMREF_PARTIAL_OUTPUT 0x0000000E
#define TEEC_MEMREF_PARTIAL_INOUT 0x0000000F

/**
 * Flag constants indicating the data transfer direction of memory in
 * TEEC_Parameter. TEEC_MEM_INPUT signifies data transfer direction from the
 * client application to the TEE. TEEC_MEM_OUTPUT signifies data transfer
 * direction from the TEE to the client application. Type is uint32_t.
 *
 * TEEC_MEM_INPUT   The Shared Memory can carry data from the client
 *                  application to the Trusted Application.
 * TEEC_MEM_OUTPUT  The Shared Memory can carry data from the Trusted
 *                  Application to the client application.
 */
#define TEEC_MEM_INPUT 0x00000001
#define TEEC_MEM_OUTPUT 0x00000002

/**
 * Return values. Type is TEEC_Result
 *
 * TEEC_SUCCESS                 The operation was successful.
 * TEEC_ERROR_GENERIC           Non-specific cause.
 * TEEC_ERROR_ACCESS_DENIED     Access privileges are not sufficient.
 * TEEC_ERROR_CANCEL            The operation was canceled.
 * TEEC_ERROR_ACCESS_CONFLICT   Concurrent accesses caused conflict.
 * TEEC_ERROR_EXCESS_DATA       Too much data for the requested operation was
 *                              passed.
 * TEEC_ERROR_BAD_FORMAT        Input data was of invalid format.
 * TEEC_ERROR_BAD_PARAMETERS    Input parameters were invalid.
 * TEEC_ERROR_BAD_STATE         Operation is not valid in the current state.
 * TEEC_ERROR_ITEM_NOT_FOUND    The requested data item is not found.
 * TEEC_ERROR_NOT_IMPLEMENTED   The requested operation should exist but is not
 *                              yet implemented.
 * TEEC_ERROR_NOT_SUPPORTED     The requested operation is valid but is not
 *                              supported in this implementation.
 * TEEC_ERROR_NO_DATA           Expected data was missing.
 * TEEC_ERROR_OUT_OF_MEMORY     System ran out of resources.
 * TEEC_ERROR_BUSY              The system is busy working on something else.
 * TEEC_ERROR_COMMUNICATION     Communication with a remote party failed.
 * TEEC_ERROR_SECURITY          A security fault was detected.
 * TEEC_ERROR_SHORT_BUFFER      The supplied buffer is too short for the
 *                              generated output.
 * TEEC_ERROR_TARGET_DEAD       Trusted Application has panicked
 *                              during the operation.
 */

/**
 *  Standard defined error codes.
 */
#define TEEC_SUCCESS 0x00000000
#define TEEC_ERROR_STORAGE_NOT_AVAILABLE 0xF0100003
#define TEEC_ERROR_GENERIC 0xFFFF0000
#define TEEC_ERROR_ACCESS_DENIED 0xFFFF0001
#define TEEC_ERROR_CANCEL 0xFFFF0002
#define TEEC_ERROR_ACCESS_CONFLICT 0xFFFF0003
#define TEEC_ERROR_EXCESS_DATA 0xFFFF0004
#define TEEC_ERROR_BAD_FORMAT 0xFFFF0005
#define TEEC_ERROR_BAD_PARAMETERS 0xFFFF0006
#define TEEC_ERROR_BAD_STATE 0xFFFF0007
#define TEEC_ERROR_ITEM_NOT_FOUND 0xFFFF0008
#define TEEC_ERROR_NOT_IMPLEMENTED 0xFFFF0009
#define TEEC_ERROR_NOT_SUPPORTED 0xFFFF000A
#define TEEC_ERROR_NO_DATA 0xFFFF000B
#define TEEC_ERROR_OUT_OF_MEMORY 0xFFFF000C
#define TEEC_ERROR_BUSY 0xFFFF000D
#define TEEC_ERROR_COMMUNICATION 0xFFFF000E
#define TEEC_ERROR_SECURITY 0xFFFF000F
#define TEEC_ERROR_SHORT_BUFFER 0xFFFF0010
#define TEEC_ERROR_EXTERNAL_CANCEL 0xFFFF0011
#define TEEC_ERROR_TARGET_DEAD 0xFFFF3024
#define TEEC_ERROR_STORAGE_NO_SPACE 0xFFFF3041

/**
 * Function error origins, of type TEEC_ErrorOrigin. These indicate where in
 * the software stack a particular return value originates from.
 *
 * TEEC_ORIGIN_API          The error originated within the TEE Client API
 *                          implementation.
 * TEEC_ORIGIN_COMMS        The error originated within the underlying
 *                          communications stack linking the rich OS with
 *                          the TEE.
 * TEEC_ORIGIN_TEE          The error originated within the common TEE code.
 * TEEC_ORIGIN_TRUSTED_APP  The error originated within the Trusted Application
 *                          code.
 */
#define TEEC_ORIGIN_API 0x00000001
#define TEEC_ORIGIN_COMMS 0x00000002
#define TEEC_ORIGIN_TEE 0x00000003
#define TEEC_ORIGIN_TRUSTED_APP 0x00000004

/**
 * Session login methods, for use in TEEC_OpenSession() as parameter
 * connectionMethod. Type is uint32_t.
 *
 * TEEC_LOGIN_PUBLIC    	 No login data is provided.
 * TEEC_LOGIN_USER         	Login data about the user running the Client
 *                         	Application process is provided.
 * TEEC_LOGIN_GROUP        	Login data about the group running the Client
 *                         	Application process is provided.
 * TEEC_LOGIN_APPLICATION  	Login data about the running Client Application
 *                         	itself is provided.
 * TEEC_LOGIN_USER_APPLICATION  Login data about the user and the running
 *                          	Client Application itself is provided.
 * TEEC_LOGIN_GROUP_APPLICATION Login data about the group and the running
 *                          	Client Application itself is provided.
 */
#define TEEC_LOGIN_PUBLIC 0x00000000
#define TEEC_LOGIN_USER 0x00000001
#define TEEC_LOGIN_GROUP 0x00000002
#define TEEC_LOGIN_APPLICATION 0x00000004
#define TEEC_LOGIN_USER_APPLICATION 0x00000005
#define TEEC_LOGIN_GROUP_APPLICATION 0x00000006

/**
 * Encode the paramTypes according to the supplied types.
 *
 * @param p0 The first param type.
 * @param p1 The second param type.
 * @param p2 The third param type.
 * @param p3 The fourth param type.
 */
#define TEEC_PARAM_TYPES(p0, p1, p2, p3) ((p0) | ((p1) << 4) | ((p2) << 8) | ((p3) << 12))

/**
 * Get the i_th param type from the paramType.
 *
 * @param p The paramType.
 * @param i The i-th parameter to get the type for.
 */
#define TEEC_PARAM_TYPE_GET(p, i) (((p) >> (i * 4)) & 0xF)

    typedef uint32_t TEEC_Result;

    /**
     * struct TEEC_Context - Represents a connection between a client application
     * and a TEE.
     */
    typedef struct
    {
        /* Implementation defined */
        int fd;
        bool reg_mem;
        bool memref_null;
    } TEEC_Context;

    /**
     * This type contains a Universally Unique Resource Identifier (UUID) type as
     * defined in RFC4122. These UUID values are used to identify Trusted
     * Applications.
     */
    typedef struct
    {
        uint32_t timeLow;
        uint16_t timeMid;
        uint16_t timeHiAndVersion;
        uint8_t clockSeqAndNode[8];
    } TEEC_UUID;

    /**
     * struct TEEC_SharedMemory - Memory to transfer data between a client
     * application and trusted code.
     *
     * @param buffer      The memory buffer which is to be, or has been, shared
     *                    with the TEE.
     * @param size        The size, in bytes, of the memory buffer.
     * @param flags       Bit-vector which holds properties of buffer.
     *                    The bit-vector can contain either or both of the
     *                    TEEC_MEM_INPUT and TEEC_MEM_OUTPUT flags.
     *
     * A shared memory block is a region of memory allocated in the context of the
     * client application memory space that can be used to transfer data between
     * that client application and a trusted application. The user of this struct
     * is responsible to populate the buffer pointer.
     */
    typedef struct
    {
        void *buffer;
        size_t size;
        uint32_t flags;
        /*
         * Implementation-Defined
         */
        int id;
        size_t alloced_size;
        void *shadow_buffer;
        int registered_fd;
        union
        {
            bool dummy;
            uint8_t flags;
        } internal;
    } TEEC_SharedMemory;

    /**
     * struct TEEC_TempMemoryReference - Temporary memory to transfer data between
     * a client application and trusted code, only used for the duration of the
     * operation.
     *
     * @param buffer  The memory buffer which is to be, or has been shared with
     *                the TEE.
     * @param size    The size, in bytes, of the memory buffer.
     *
     * A memory buffer that is registered temporarily for the duration of the
     * operation to be called.
     */
    typedef struct
    {
        void *buffer;
        size_t size;
    } TEEC_TempMemoryReference;

    /**
     * struct TEEC_RegisteredMemoryReference - use a pre-registered or
     * pre-allocated shared memory block of memory to transfer data between
     * a client application and trusted code.
     *
     * @param parent  Points to a shared memory structure. The memory reference
     *                may utilize the whole shared memory or only a part of it.
     *                Must not be NULL
     *
     * @param size    The size, in bytes, of the memory buffer.
     *
     * @param offset  The offset, in bytes, of the referenced memory region from
     *                the start of the shared memory block.
     *
     */
    typedef struct
    {
        TEEC_SharedMemory *parent;
        size_t size;
        size_t offset;
    } TEEC_RegisteredMemoryReference;

    /**
     * struct TEEC_Value - Small raw data container
     *
     * Instead of allocating a shared memory buffer this structure can be used
     * to pass small raw data between a client application and trusted code.
     *
     * @param a  The first integer value.
     *
     * @param b  The second value.
     */
    typedef struct
    {
        uint32_t a;
        uint32_t b;
    } TEEC_Value;

    /**
     * union TEEC_Parameter - Memory container to be used when passing data between
     *                        client application and trusted code.
     *
     * Either the client uses a shared memory reference, parts of it or a small raw
     * data container.
     *
     * @param tmpref  A temporary memory reference only valid for the duration
     *                of the operation.
     *
     * @param memref  The entire shared memory or parts of it.
     *
     * @param value   The small raw data container to use
     */
    typedef union
    {
        TEEC_TempMemoryReference tmpref;
        TEEC_RegisteredMemoryReference memref;
        TEEC_Value value;
    } TEEC_Parameter;

    /**
     * struct TEEC_Session - Represents a connection between a client application
     * and a trusted application.
     */
    typedef struct
    {
        /* Implementation defined */
        TEEC_Context *ctx;
        uint32_t session_id;
    } TEEC_Session;

    /**
     * struct TEEC_Operation - Holds information and memory references used in
     * TEEC_InvokeCommand().
     *
     * @param   started     Client must initialize to zero if it needs to cancel
     *                      an operation about to be performed.
     * @param   paramTypes  Type of data passed. Use TEEC_PARAM_TYPES macro to
     *                      create the correct flags.
     *                      0 means TEEC_NONE is passed for all params.
     * @param   params      Array of parameters of type TEEC_Parameter.
     * @param   session     Internal pointer to the last session used by
     *                      TEEC_InvokeCommand with this operation.
     *
     */
    typedef struct
    {
        uint32_t started;
        uint32_t paramTypes;
        TEEC_Parameter params[TEEC_CONFIG_PAYLOAD_REF_COUNT];
        /* Implementation-Defined */
        TEEC_Session *session;
    } TEEC_Operation;

    /**
     * TEEC_InitializeContext() - Initializes a context holding connection
     * information on the specific TEE, designated by the name string.

     * @param name    A zero-terminated string identifying the TEE to connect to.
     *                If name is set to NULL, the default TEE is connected to. NULL
     *                is the only supported value in this version of the API
     *                implementation.
     *
     * @param context The context structure which is to be initialized.
     *
     * @return TEEC_SUCCESS  The initialization was successful.
     * @return TEEC_Result   Something failed.
     */
    TEEC_Result TEEC_InitializeContext(const char *name, TEEC_Context *context);

    /**
     * TEEC_FinalizeContext() - Destroys a context holding connection information
     * on the specific TEE.
     *
     * This function destroys an initialized TEE context, closing the connection
     * between the client application and the TEE. This function must only be
     * called when all sessions related to this TEE context have been closed and
     * all shared memory blocks have been released.
     *
     * @param context       The context to be destroyed.
     */
    void TEEC_FinalizeContext(TEEC_Context *context);

    /**
     * TEEC_OpenSession() - Opens a new session with the specified trusted
     *                      application.
     *
     * @param context            The initialized TEE context structure in which
     *                           scope to open the session.
     * @param session            The session to initialize.
     * @param destination        A structure identifying the trusted application
     *                           with which to open a session.
     *
     * @param connectionMethod   The connection method to use.
     * @param connectionData     Any data necessary to connect with the chosen
     *                           connection method. Not supported, should be set to
     *                           NULL.
     * @param operation          An operation structure to use in the session. May
     *                           be set to NULL to signify no operation structure
     *                           needed.
     *
     * @param returnOrigin       A parameter which will hold the error origin if
     *                           this function returns any value other than
     *                           TEEC_SUCCESS.
     *
     * @return TEEC_SUCCESS      OpenSession successfully opened a new session.
     * @return TEEC_Result       Something failed.
     *
     */
    TEEC_Result TEEC_OpenSession(TEEC_Context *context, TEEC_Session *session,
                                 const TEEC_UUID *destination, uint32_t connectionMethod,
                                 const void *connectionData, TEEC_Operation *operation,
                                 uint32_t *returnOrigin);

    /**
     * TEEC_CloseSession() - Closes the session which has been opened with the
     * specific trusted application.
     *
     * @param session The opened session to close.
     */
    void TEEC_CloseSession(TEEC_Session *session);

    /**
     * TEEC_InvokeCommand() - Executes a command in the specified trusted
     * application.
     *
     * @param session        A handle to an open connection to the trusted
     *                       application.
     * @param commandID      Identifier of the command in the trusted application
     *                       to invoke.
     * @param operation      An operation structure to use in the invoke command.
     *                       May be set to NULL to signify no operation structure
     *                       needed.
     * @param returnOrigin   A parameter which will hold the error origin if this
     *                       function returns any value other than TEEC_SUCCESS.
     *
     * @return TEEC_SUCCESS  OpenSession successfully opened a new session.
     * @return TEEC_Result   Something failed.
     */
    TEEC_Result TEEC_InvokeCommand(TEEC_Session *session, uint32_t commandID,
                                   TEEC_Operation *operation, uint32_t *returnOrigin);

    /**
     * TEEC_RegisterSharedMemory() - Register a block of existing memory as a
     * shared block within the scope of the specified context.
     *
     * @param context    The initialized TEE context structure in which scope to
     *                   open the session.
     * @param sharedMem  pointer to the shared memory structure to register.
     *
     * @return TEEC_SUCCESS              The registration was successful.
     * @return TEEC_ERROR_OUT_OF_MEMORY  Memory exhaustion.
     * @return TEEC_Result               Something failed.
     */
    TEEC_Result TEEC_RegisterSharedMemory(TEEC_Context *context, TEEC_SharedMemory *sharedMem);

    /**
     * TEEC_AllocateSharedMemory() - Allocate shared memory for TEE.
     *
     * @param context     The initialized TEE context structure in which scope to
     *                    open the session.
     * @param sharedMem   Pointer to the allocated shared memory.
     *
     * @return TEEC_SUCCESS              The registration was successful.
     * @return TEEC_ERROR_OUT_OF_MEMORY  Memory exhaustion.
     * @return TEEC_Result               Something failed.
     */
    TEEC_Result TEEC_AllocateSharedMemory(TEEC_Context *context, TEEC_SharedMemory *sharedMem);

    /**
     * TEEC_ReleaseSharedMemory() - Free or deregister the shared memory.
     *
     * @param sharedMem  Pointer to the shared memory to be freed.
     */
    void TEEC_ReleaseSharedMemory(TEEC_SharedMemory *sharedMemory);

    /**
     * TEEC_RequestCancellation() - Request the cancellation of a pending open
     *                              session or command invocation.
     *
     * @param operation Pointer to an operation previously passed to open session
     *                  or invoke.
     */
    void TEEC_RequestCancellation(TEEC_Operation *operation);

#ifdef __cplusplus
}
#endif

#endif
